diff --git a/alias.go b/alias.go
index 3afb04b..5e53222 100644
--- a/alias.go
+++ b/alias.go
@@ -106,8 +106,7 @@ func handleAliasCommand() {
 		replacecmd.SetOutput(os.Stdout)
 		cfgpath := replacecmd.String("config", "", "path to configuration")
 		aname := replacecmd.String("name", "", "(required) name of alias")
-		oiname := replacecmd.String("oldindex", "",
-			"(required) name of the old index")
+		oiname := replacecmd.String("oldindex", "", "name of the old index")
 		niname := replacecmd.String("newindex", "",
 			"(required) name of the new index")
 		replacecmd.Parse(os.Args[3:])
@@ -117,12 +116,7 @@ func handleAliasCommand() {
 			replacecmd.PrintDefaults()
 			os.Exit(1)
 		}
-		if *oiname == "" {
-			fmt.Fprintf(os.Stderr,
-				"oldindex parameter is required for alias replace\n")
-			replacecmd.PrintDefaults()
-			os.Exit(1)
-		}
+
 		if *niname == "" {
 			fmt.Fprintf(os.Stderr,
 				"newindex parameter is required for alias replace\n")
@@ -133,10 +127,29 @@ func handleAliasCommand() {
 		cfg := LoadConfig(*cfgpath)
 		es := ClientFromConfig(cfg.Elastic)
 
-		_, err := es.Alias().
-			Remove(*oiname, *aname).
-			Add(*niname, *aname).
-			Do(context.Background())
+		oinames := make([]string, 0, 10)
+		if *oiname != "" {
+			oinames = append(oinames, *oiname)
+		} else {
+			aliases, err := es.CatAliases().Do(context.Background())
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "elastic error: %s\n", err.Error())
+				os.Exit(1)
+			}
+
+			for _, alias := range aliases {
+				if alias.Alias == *aname {
+					oinames = append(oinames, alias.Index)
+				}
+			}
+		}
+
+		as := es.Alias()
+		for _, idx := range oinames {
+			as.Remove(idx, *aname)
+		}
+		as.Add(*niname, *aname)
+		_, err := as.Do(context.Background())
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "elastic error: %s\n", err.Error())
 			os.Exit(1)